Checks if the site appears to be using a Content Delivery Network.
A Content Delivery Network (CDN) is a network of servers distributed geographically. When you use a CDN, your website's files are stored on all these servers. Users are then served files from the server that is physically closest to them.
CDNs dramatically reduce latency and speed up page load times for users around the world. They also help handle traffic spikes and can offer additional security benefits.
For any website with a global or even national audience, using a CDN is one of the most effective ways to improve performance and reliability.
Run a free audit to see how your site performs on CDN Usage and 159 other checks.
Start Free AuditChecks if images use responsive techniques like srcset.
Checks if images have width and height attributes to prevent layout shift.
Checks for JavaScript errors in the browser console. (Note: In-dev check)
Measures the total size of the HTML document.